Arbovirusの化学的性状に関する研究
第4報 日本脳炎ウイルス組織培養継代株の2, 3の性質について
1965 年 20 巻 2-3 号 p. 101-107
詳細
1965 年 20 巻 2-3 号 p. 101-107
Japaneses B encephalitis (JBE) virus investigated was Gl strain which was serially passaged into primary hamster kidney tissue cultures more than 150 generations. The virus infected culture fluid was used in the following experiments and this was designated as “TC strain”.
On the other hand, the mouse-passaged original JBE virus (Gl strain) of more than 250 generations was also used for comparison with the former and designated as “M strain”.
Some experimental methods and results obtained are summarized as follows:
(1) The chromatographic behavior of the M and TC strain viruses on DEAE-cellulose column:
Each virus suspension diluted in the medium was load onto DEAE-cellulose column and eluted with 0.07M phosphate buffer (PH 7.2) increasing stepwise from 0.1 to 0.6M NaCl. The eluates were fractionated in every 10ml and their viral contents were assayed by inoculating into hamster kidney cell cultures.
From these results obtained, it was found that more than 74% of the TC strain virus was recovered in earlier fractions (1 to 6) of the effluent and its elution pattern showed a simple curve. On the contrary, the M strain virus was slowly eluted from the cellulose column.
(2) Interaction between the viruses and some animal tissue homogenates:
Each virus suspension was mixed with the tissue homogenates, incubated at 37°C for 2 hours, and then centrifuged at 15, 000rpm for 30 minutes. The infectivity of residual active virus in the supernatant fluid was titrated by inoculating into either mice or hamster kidney cell cultures. The infectivity of M strain virus was completely inactivated by the brain tissue but not liver or kidney tissue homogenates of mice. On the the other hand, the infectivity of the TC strain virus was affected, to similar extents, by the brain, liver or kidney tissue homogenates of mice, and inactivated, more or less, by the liver or kidney tissue homogenates of hamster.
(3) Thermal inactivation of the viruses:
The thermal inactivation rate of both virus strains was determined at different temperature. The infectivity of the TC strain virus was completely inactivated by being heated at 55°C for 30 minutes, while about 0.01% of the TC strain virus had shown the viral infectivity. After incubation at 40°C for 120 minutes, about 1.7% of the TC strain virus remained active and, on the contrary, the surviving rate of the M strain virus was only 0.1% under the same condition.
